Hey there! Want to know a secret? We’ve got the inside scoop on the best spot to mount a red dot sight on your AR-15. And guess what? It’s not on that fancy freefloat handguard rail. Stick with us as we walk you through it.
Table of Contents
Can You Mount a Red Dot on the Handguard?
Before we dive in, let us give you our recommendation: Mount your red dot optic on the rifle’s receiver. Avoid placing it on the handguard. Here’s why:
The receiver is more stable than the handguard, which is prone to vibrations and play. This instability can throw off your optic’s zero. To ensure accuracy, mount your red dot on top of the receiver.
AR15s can get pretty dirty, especially the gas system. Cleaning the gas system and barrel requires removing the handguard. If your red dot is mounted on the handguard, you’ll have to re-zero it every time you clean your rifle.
Some folks swap their uppers from rifle to rifle. Mounting the optic on the handguard increases the risk of accidental adjustment. By mounting the dot on the receiver, you’ll have a better chance of maintaining zero when transferring to a new lower.
How Should You Mount Your Red Dot on Your AR-15?
As a general rule, mount your 1x red dot optic as far forward as possible. This applies to all types of red dot sights that lack magnification, whether they’re tubular, reflex, or holographic.
Why? The purpose of using a 1x red dot is to shoot with both eyes open and enhance your peripheral vision. Placing the optic far forward reduces obstruction, allowing for up to 30% increased peripheral vision and situational awareness. Say goodbye to tunnel vision! One popular red dot sight for AR15 rifles is the AT3 Alpha – check it out in this video!
A good guideline is to align the front of your red dot mount with the second picatinny section on your receiver. This maximizes peripheral vision and provides extra room for removing the handguard.
What Are the Benefits of a Cantilever Mount?
Some optics may be mounted forward over the handguard but still allow handguard removal without re-zeroing the optic. That’s perfectly fine! If you’re curious about removing an old-school A2/M4 carbine handguard, make sure to check out this free army service manual for the AR15!
Where Should the Dot Be on Your Optic?
Here’s an important tip: Ensure that your eye line aligns with the center of the optic when shouldering the rifle. If you have the correct mount, this alignment should be achieved regardless of how far forward your optic is mounted. If you find yourself adjusting your head position, you may need a different riser mount.
If you’re pairing your red dot sight with backup iron sights, take a look at our article on Absolute vs Lower 1/3 Cowitness Sights!
How Far Back Should You Mount a Red Dot?
At AT3 Tactical, we encourage mounting most red dot optics as far forward as possible on the upper receiver, avoiding the handguard. However, comfort and practicality should also factor into your decision. Remember, everyone starts somewhere, so a little trial and error is perfectly fine.
Interested in seeing some guns with mounted red dot sights? Check out this article: How To Choose a Red Dot – A Buyer’s Guide to AT3 Optics.
One Last Tip
When it comes to the AR-15 platform, nobody knows it better than the US military. As a special offer for our readers, you can get the Official US Army Manual for AR-15/M4/M16 for free. Click here to grab your copy!